$ZCHSET is a read-only intrinsic special variable that takes its value from the environment variable gtm_chset. An application can obtain the character set used by a GT.M process by the value of $ZCHSET. $ZCHSET can have only two values --"M", or "UTF-8".

GT.M only supports Unicode on certain platforms. On platforms where it is not supported, the intrinsic variable $ZCHSET is always "M" ignoring the value of the environment variable gtm_chset even if it is defined.

Example:

$ export gtm_chset=UTF-8
$ /usr/lib/fis-gtm/V6.0-001_x86/gtm
GTM>write $zchset
UTF-8
GTM>